Progressive stamping device having work stations in a curvilinear path

ABSTRACT

An automatic stamping machine for stamping by means of punches of metal articles from a feed strip and performing various work operations thereon in which the work stations are mounted in a curved pattern on the periphery of at least one or more interacting rotatable segments. The work path thus follows a sinuous line. The machine is provided with a central guide shaft that guides both the vertical and lateral movement of the mechanism. In addition, the central shaft serves as a guide for auxiliary devices, for example, such as the punch knock out and switching mechanisms. The mechanism has a top and bottom set of rollers engaging the central shaft and a set of needle bearings which eliminate the tendency toward binding of the mechanism.

United States Patent [191 Hakner Aug. 27, 1974 PROGRESSIVE STAMPINGDEVICE HAVING WORK STATIONS IN A CURVILINEAR PATH [76] Inventor: RobertHakner, 76-78 Vernon Ave.,

Brooklyn, NY. 11206 [22] Filed: Sept. 29, 1972 [21] Appl. No.: 293,413

52 us. Cl. 72/405 [51] Int. Cl B21d 43/00 [58] Field of Search 113/1 F;29/208 F, 33 J, 29/37 R, 36, 38 A, 563; 72/405 [56] References CitedUNITED STATES PATENTS 3,245,370 4/1966 Bofinger 113/1 3,371,514 3/1968Venables 72/420 3,534,582 10/1970 Hakner 72/405 3,571,873 3/1971 Muller29/38 3,616,513 11/1971 3,735,470 5/1973 Elmer et al 29/208 F PrimaryExaminer-Charles W. Lanham Assistant Examiner-M. .1. Keenan Attorney,Agent, or Firm-Alfred E. Miller ABSTRACT An automatic stamping machinefor stamping by means of punches of metal articles from a feed strip andperforming various work operations thereon in which the work stationsare mounted in a curved pattern on the periphery of at least one or moreinteracting rotatable segments. The work path thus follows a sinuousline. The machine is provided with a central guide shaft that guidesboth the vertical and lateral movement of the mechanism. In addition,the central shaft serves as a guide for auxiliary devices, for example,such as the punch knock out and switching mechanisms. The mechanism hasa top and bottom set of rollers engaging the central shaft and a set ofneedle bearings which eliminate the tendency toward binding of themechanism.

11 Claims, 11 Drawing Figures A ,5? I l til. l lz t wg i lUQlQ G QlPATENTEDAUBZYIQH' 3.831.426

SHEET 50$ 6 The present invention relates to an automatic stampingmechanism for metal articles wherein the work stations are arranged in acurved or circular pattern thereby simplifying the structure andimproving the guidance resulting in a smooth and precision-typemechanism. The present apparatus further includes a rotatablyreciprocating independent segment or segments. If a plurality ofsegments are employed there may be different spacing between the stagesof operation.

An object of the present inventionis to provide stan dardized die setssuitable for die manufactures to incorporate in tools for automaticstamping which can be accomplished more conveniently and lessexpensively than heretofore.

A further object of the present invention is to provide a central guideshaft for both the vertical and lateral movement of the mechanism. Thecentral shaft controls, in part, the alignment of opposing punches anddies. It also serves as a guide for auxiliary devices such as the punchknock-out bushing, switching mechanisms, guide pins or bushings forprecision alignment.

Another object of the present invention is to provide for the dischargeof scrap resulting from the trimming and piercing of the work pieces.This is accomplished by the use of a complete indexing segment in whichthe punch and die meet each other after every second stroke of themachine.

Heretofore, progressive stamping has been carried out in a linear mannerwhich required a longer, spaceconsuming construction. On the other hand,the present invention consists of metal stamping machine having a numberof curved segments which intermesh in order to transfer the work fromstation to station whereby the work path follows a sinuous line; thus,the work pieces can be transferred from one rotatable segment to theadjacent rotatable segment. Thus, the work is performed in a closerarea.

It is another object of the present invention to provide automaticstamping of metal articles in which the work stations are arranged tofollow a curved or completely circular path. The mechanism automaticallytransfers the work from one segment to the adjacent or consecutivesegment.

It is a further object of the present invention to provide an automaticstamping mechanism for the progressive stamping of metal articles whichis provided with a central shaft encircled by a bushing. The bushingsupports a series of hollow punches mounted circularly on a rotatablecarrier. Each of the punches is provided on the periphery of the carrierand includes a punch knockout. The arrangement is further provided witha top and bottom set of rollers within the bushing which engages thecentral shaft and since there is lateral movement a further set ofneedle bearings are provided which have the desirable function ofeliminating any tendency of the bushing and central shaft binding.

The invention will now be more fully described with reference to theaccompanying drawings wherein:

FIG. 1 is a view of a rotatable segment for an automatic stampingmechanism constructed in accordance with the teachings of the presentinvention and taken along the lines 1-] of FIG. 2.

FIG. 2 is a cross-sectional view taken along the lines 2-2 of FIG. 1.

FIG. 3 is a top plan view showing two rotatable segments of the presentmechanism interacting in accordance with the teachings of the presentinvention.

FIGS. 4, 5, 6, and 7 are partial sectional and partial side elevationalviews of the rotatable segment together with the hollow punch, knockout,pawl and catch arrangement, shown in various positions during thevertical movement of the central shaft.

FIG. 8 is a further top plan view showing spaced rotatable segments 10and an intermediate table rotating continuously in one direction.

FIG. 9 is a modification of the present invention showing a segmentlOtogether with the associated structure and having sets of upper andlower rollers engaging the central shaft.

FIG. 10 is a further top plan view showing a rotatable segment 10 andslots therein which permit the segment to reciprocate and the device tobe lowered and elevate'd.

FIG. 1 1 is a top plan view of the pawl and ratchet arrangement forindexing segments relative to each other.

Referring to FIG. I, it should be understood that the segment 10 canmake a partial reciprocating rotary movement or a full circularmovement. Aseries of hollow punches 12 are mounted circularly on therotatable carrier 14. The carrier 14 has an upstanding shank 15 which isshown displaced from the center of the carrier and is designed to befastened to a well-known powered ram (not shown). Each punch 12 isprovided with a punch knockout l6, movable vertically within the hollowpunch. As seen in FIG. 2, each punch knockout 16 is normally held in anelevated position within the hollow punch 12 by means of a helicalspring 18. The height of punch knockout 16 may be selectively portionsby means of a slidable rod 20 in bushing 22. Screw-threaded nuts 24 areadjustable on the threaded portiosn of rod 20 in order to vary theheight of the punch knockout l6.

It will be noted that the carrier 14 rotates while the central shaft 26merely moves up and down.

As seen in FIG. 1, a cam arrangment referred to gen erally by the number30 may be utilized for effecting the stepped movements of the rotatablesegment 10 such as that shown by me in my US. Pat. No. 3,534,582 exceptthat as shown in FIGS. 8-11, the roller 50 may be eliminated and a rodor other projection may be utilized to'operate the triangular shaped cam46 linearly behind the central shaft 26. The hollow punches 12 punch thework piece out of the strip 32 and pass the piece from work station towork station in a curvilinear path. As seen in FIG. 3, adjacent segments10 work in synchronism so that the work piece follows the path indicatedby the arrows and consequently form a sinuous pattern. As shown in fulllines in FIG. 3, the left hand segment 10 moves backwards to permit theright hand segment to pick up the work piece W.

As seen in FIG. 2, a pivotable latch 34 is pivotably secured to bushing22. The latch 34 has a spring-loaded finger 46 which nomially urges thelatch 34 toward the central shaft 26. Secured to the base member 38 ofthe mechanism is a hasp or catch 40 for receiving the As seen in FIG. I,the metal strip 32 is shown moving I hooked end 34a of the latch 34. Thehasp 40 is pivotably mounted at 42 to the base member 38 and is engagedat the opposite end by another spring-loaded finger 44. It should benoted that the central shaft 26 is provided with an indentation 47 whichis complementary to a corresponding projection 34b of the latch 34.Thus, when the central shaft 26 is moved downwardly, as seen in FIGS. 4and 5, the lever 34 has its projection 34b drop into the complementaryindentation 47. When this occurs, the hooked end 340 of the lever 34 isengaged in hasp 40 and spring-loaded finger 46 maintains the lever 34 inits hooked condition, and the carrier 14 and punch 12 are held in astationary position while the knockout 16 continues downwardly andseparates the workpiece form the punch, while the latter moves upwardly.

As seen in FIGS. 6 and 7, the central shaft 26 moves upwardly due to theaction of cam arrangement 30 and when this occurs, the lever 34 iscammed out of the indentation 47 in the shaft 26, thus releasing thecarrier 14 for movement both vertically and rotationally. As seen inFIG. 6, there is a space f between the carrier 14 and the bushing 22which permits the latter to move vertically. It should also be notedthat the present machine, even though operating in a semirotary manner,has linear characteristics.

FIG. 8 is a diagrammatic view showing the method of operation of thepresent invention showing two spaced rotatable segments and a fullyrotatable circular disc table 62 which is located between and below saidsegments 10. It will e noted that the segments 10 engage inreciprocating rotation or pivoting action while the table 62 rotatesfully but only continuously in one direction. The present arrangement issuch that the work pieces are worked on only in every other position. Inthe positions between the work positions are holes 64 through which thetrimming and piercing scrap on the work pieces are ejected. Thus, everyother station is a stripping station in the present apparatus.

FIG. 9 discloses an arrangement in which the central shaft 26 isprovided with a bushing 22 having a set of rollers 66 located at the topof the bushing 22 and another set of rollers 68 located adjacent to thebottom of bushing 22. It should be noted that the construction shownherein results in a smooth functioning of the central shaft 26 withinthe bushing 22 when the punch knockout 16 functions, and eliminates anytendency of the two interengaging elements to bind.

The bushing 22 is provided with a spring-urged adjustable stop member70. The base member 38 has a spring-biased, upwardly directed finger 72that engages the undersurface of one end of an elongated bar 74. The bar74 is pivotable on the pivot 76 and is provide with an end 740. A hookmember 78 is pivoted on the pivot 79 and engages the end 74a of the bar74. The enlarged end 78a of the hook member 78 is cammed on cam surface81 upon the upward movement of central shaft 26 thereby disconnectingthe hook end 78a from the bar end 740. It should be noted that themovement of the shaft 26 upwardly will automatically clear the hook andcatch arrangement thereby permitting the bushing 22 and the rotatablesegment 14 to be elevated.

FIG. 10 shows a top plan view of a reciprocating segment 10 in whichslots 63 are shown through which the threaded pins 65 project. Theconstruction is such that the segment 10 is permitted to reciprocate toaccomplish article feed as well as to move vertically respon sive to theactivation of the powered ram.

FIG. 11 shows the preferred form of rotating a segment continuously inone direction by means of a reciprocating segment In the illustration,adjacent segments 10a and 10b are shown in which reciprocating segment10a is provided with a pawl arm having a pawl 92 that is adapted toengage a ratchet wheel 94 on the segment 1012. A spring biased holdingpawl 96 for engaging the ratchet wheel 94 is also shown. The action ofthe pawl 92 on on the ratchet wheel 94 functions to cause the segment10b to rotate continuously in one direction even though the segment 10areciprocates, as indicated by the arrows. The number of teeth on theratchet wheel 94 may be varied in accordance with the number of stationsrequired for the present machine.

It should be noted that the triangular shaped cam 46, as seen in FIG. 1,may be moved to a position which is radially displaced from the locationshown. This position permits a longer stroke of the stamping andtransferring mechanism shown herein.

What is claimed is:

1. An automatic stamping mechanism for metal articles which require morethan one operation performed thereon and in which the same tools thatperform the stamping also transfer the articles to successive stages ofoperation in a curved line comprising: a die bed, at lease one rotatablyreciprocating segment which additionally moves vertically, each segmentbeing provided with spaced punches mounted in a curved pattern, meansmounting said segment for movement in a curvilinear path, means forlimiting the movement of said segment in a substantially vertical plane,and a central post element acting as a guide axis for vertical androtatable movement of said segment.

2. An automatic stamping mechanism as claimed in claim 1 furtherproviding a disc table located adjacent to but in a plane below theplane of said segment, said disc table rotating continuously in onedirection and in an opposite direction to the movement of said segment,and constituting alternate work stations and holes through which thetrimming and piercing scrap on the work pieces are ejected.

3. An automatic stamping mechanism as claimed in claim 1 wherein eachsegment is provided with selected same or different spacing of saidpunches thereon.

4. An automatic stamping mechanism for progressive stamping of metalarticles which require more than one operation performed thereon and inwhich the same tools that perform the stamping also transfer thearticles to successive stages of operation comprising: a stationary diebed, a plurality of rotatable segments which additionally selectivelymove vertically, each of the segments being provided withspaced hollowpunches mounted in a curved pattern, means mounting said segments formovement in a curvilinear path whereby said metal articles aretransferred from one rotatable segment to an adjacent rotatable segment,a punch knockout operable within each of said hollow punches, a bushingfor said rotable segments, a pawl operatively connected to said bushing,a catch for said pawl mounted on said die bed, said pawl engaging saidcatch when said bushing of the rotatable segment moves verticallydownwardly. and a central shaft movable vertically and having meansthereon whereby when said shaft moves upwardly said means disengagessaid pawl from said catch after said punch knockout functions to ejectthe metal article in the punch holder, and said rotable segments aremovable relative to said stationary die bed.

5. An automatic stamping mechanism for progressive stamping of metalarticles as claimed in claim 4 further comprising upper and lower set ofrollers, mounted on said bushing for rolling engagement with saidcentral shaft.

6. An automatic stamping mechanism for progressive stamping of metalarticles as claimed in claim 4, wherein said pawl is provided with aperipheral projection adjacent to said central shaft, and said means onthe central shaft for co-acting with said peripheral projection is agroove whereby when said projection drops in said groove the upwardmovement of said central shaft cams said pawl out of engagement withsaid catch.

7. An automatic stamping mechanism for progressive stamping of metalarticles as claimed in claim 4, wherein said catch is spring-urged andpivotally mounted on said die bed.

8. An automatic stamping mechanism as claimed in claim 4 furthercomprising means for adjusting the height of said punch knockoutrelative to said die bed.-

said work is discharged or scrap therefrom ejected.

* l =l =I= UNITED STATES PATENT OF FI CE I 1 CERTIFICATE OF CORRECTIONPatent No. I 3, 3 Dated ugust27, 1974 Inventor(s) ROBERT HAKNER It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, line 36, after "of", there should be an --a--. Column 2, lines37- 38, portions" should. be --'-adjusted- Column 2, line 40, 'portiosn"should be --por tio'ns-. Column 3, line 31, f'e," should be --be--. 1

C l 3, in 53,...'i'p v el b lld ber-p id d-w v s r In Claim 3, line 3,de1ete."s'ame or".

Signed and sealed this 7th day of"Ja,nuary 1975.

(SEAL) Attest: I

McCOY M. GIBSON JR. "c. MARSHALL DANN Attesting Officer r Commissionerof Patents FORM po-wso (IO-69) USCOMM-DC scan-Pea u.s. coviulnllin:PRINTING orilc: I"! o-a'ia-m.

1. An automatic stamping mechanism for metal articles which require morethan one operation performed thereon and in which the same tools thatperform the stamping also transfer the articles to successive stages ofoperation in a curved line comprising: a die bed, at lease one rotatablyreciprocating segment which additionally moves vertically, each segmentbeing provided with spaced punches mounted in a curved pattern, meansmounting said segment for movement in a curvilinear path, means forlimiting the movement of said segment in a substantially vertical plane,and a central post element acting as a guide axis for vertical androtatable movement of said segment.
 2. An automatic stamping mechanismas claimed in claim 1 further providing a disc table located adjacent tobut in a plane below the plane of said segment, said disc table rotatingcontinuously in one direction and in an opposite direction to themovement of said segment, and constituting alternate work stations andholes through which the trimming and piercing scrap on the work piecesare ejected.
 3. An automatic stamping mechanism as claimed in claim 1wherein each segment is provided with selected same or different spacingof said punches thereon.
 4. An automatic stamping mechanism forprogressive stamping of metal articles which require more than oneoperation performed thereon and in which the same tools that perform thestamping also transfer the articles to successive stages of operationcomprising: a stationary die bed, a plurality of rotatable segmentswhich additionally selectively move vertically, each of the segmentsbeing provided with spaced hollow punches mounted in a curved pattern,means mounting said segments for movement in a curvilinear path wherebysaid metal articles are transferred from one rotatable segment to anadjacent rotatable segment, a punch knockout operable within each ofsaid hollow punches, a bushing for said rotable segments, a pawloperatively connected to said bushing, a catch for said pawl mounted onsaid die bed, said pawl engaging said catch when said bushing of therotatable segment moves vertically downwardly, and a central shaftmovable vertically and having means thereon whereby when said shaftmoves upwardly said means disengages said pawl from said catch aftersaid punch knockout functions to eject the metal article in the punchholder, and said rotable segments are movable relative to saidstationary die bed.
 5. An automatic stamping mechanism for progressivestamping of metal articles as claimed in claim 4 further comprisingupper and lower set of rollers, mounted on said bushing for rollingengagement with said central shaft.
 6. An automatic stamping mechanismfor progressive stamping of metal articles as claimed in claim 4,wherein said pawl is provided with a peripheral projection adjacent tosaid central shaft, and said means on the central shaft for co-actingwith said peripheral projection is a groove whereby when said projectiondrops in said groove the upward movement of said central shaft cams saidpawl out of engagement with said catch.
 7. An automatic stampingmechanism for progressive stamping of metal articles as claimed in claim4, wherein said catch is spring-urged and pivotally mounted on said diebed.
 8. An automatic stamping mechanism as claimed in claim 4 furthercomprising means for adjusting the height of said punch knockoutrelative to said die bed.
 9. An automatic stamping mechanism as claimedin claim 4, wherein said hollow Punches are located on each of saidsegments at a distance remote from said central shaft.
 10. An automaticstamping mechanism as claimed in claim 5 further comprising a pivotablemount for said pawl, and an adjustable stop member on said bushing whichengages said pivotable mount, the latter acting as an abutment.
 11. Anautomatic stamping mechanism as claimed in claim 1 wherein said segmentin one position has work performed on said metal article and in anotherposition said work is discharged or scrap therefrom ejected.